The Super Sports Show was about to begin at the World Congress Convention Center in Atlanta and for those of us involved in the business of sports, it was an exciting time of year. Thousands of people from across the globe had made the annual trek to one of the largest trade show events in the world. It was the mid 90s, just prior to the digital revolution, and trade shows were still a critical facilitator of business and trade relationships. It was a big deal. The show would last four or five days and big brands like Nike and Adidas would invest heavily to put on a big show for their partners and colleagues to come and enjoy themselves, see new products and do business.
Distinguished Tennis Guest
I had been to the show in Atlanta the previous year but this year was special. I had new prototypes of my experimental tennis racquet design with me and meetings with manufacturers set up. I was looking to license the design and eager to show the new racquets off. Another big highlight of the event would be the appearance of tennis legend Rod Laver to help launch a new tennis racquet. I was curious about the racquet and of course I admired Mr. Laver so I was especially fired up for the occasion.
First thing in the morning on day one of the show, I went straight to the Pro Kennex booth on the display floor to get a glimpse of the left-handed Australian tennis champ. It turned out that Mr. Laver's schedule was far more jammed up than mine, no surprise, so he wouldn't be in the booth until later. It was disappointing but it gave me time to look around. Right in front of me was the new Kinetic racquet being introduced by Pro Kennex and hailed as the next great remedy for racquet vibration and various issues of arm and wrist discomfort. Having spent the previous couple of years studying racquet patents, I was familiar with the concept of a kinetic mass design but I didn't know it was already in production. It was an eye-opener for me to see the concept realized in a real product.
Inventor In the House
Another special guest of Pro Kennex, enlisted along with Mr. Laver for the Kinetic introduction, was the inventor and engineer of the Kinetic design himself, Roland Sommer. I didn't know what he looked like but I was familiar with his racquet patents and the story behind them. He was German, with a background in aeronautical engineering. His racquet design employed a method used to reduce vibration in the making of airplane wings. As I learned from him later, it was difficult to adapt the design for mass production but he worked it out. Lucky for me his schedule wasn't packed like Mr. Laver's. His schedule was open and he was stranded at the show for the week. I figured I had at least a few days to pick his brain about everything related to racquet design and production.
By the time Mr. Laver made his way to the Pro Kennex booth for the first time, I had already gotten to know Mr. Sommer a bit. I met the great tennis champion which was a thrill but naturally he had an entourage of sorts so he wasn't really accessible for conversation. Mr. Sommer was available though, and at that point I was set on speaking with him further. I noticed he took frequent and long coffee breaks outside in the exhibition lounge so I kept my eye out for him there. As it turned out, the privacy of the lounge made it easier for us to talk. He had just gone through the entire process of development from original idea to product so the timing was right for me to learn all I could from him and try to put it to use in my project.
Headache Leads to Solution
Mr. Sommer's path to the Kinetic began when a player he knew got a tennis elbow so bad he had to stop playing. The solution was to drill a series of small holes into a wood racquet frame and fill the holes with "micro-bearings" in such a way that the micro-bearings (tiny beads) could shake around a bit in the small spaces and dissipate energy (absorb vibration). Adhesive tape is all that kept the micro-bearings in the holes but it worked enough for his friend to confirm that it reduced vibration, relieved his arm of some discomfort and eventually helped him to get back on the court. Mr. Sommer tuned up the design and secured a licensing deal with Kunnan Lo, the giant industrial engine behind a number of racquet brands at the time, including Pro Kennex.
His timing was good. It coincided with the rise of hollow tube carbon composite racquets and a serious uptick in arm and wrist injuries. The timing also made for tricky manufacturing issues which for a time made Mr. Sommer believe it may not be possible to achieve in a racquet for mass production. His prototypes had been made of wood and now the design had to be configured for a hollow tube composite construction. It was quite a dilemma and he wrestled with it for months. After much turmoil and near to throwing in the towel, he came down with a bad headache in the office one day and decided to go home early and get some rest. At home and in search of a remedy, he reached into his medicine cabinet for the 'Contac' and found both a solution to his sore head and a solution to his production problem. Just like the plastic Contac capsules filled with tiny beads of medicine and sealed into a strip of plastic, he realized his micro-bearings could be encapsulated and sealed into a plastic strip in the same way, and the strip could be located inside the hollow tube of the racquet - problem solved.
After hearing his tale and seeing it come to fruition in a new product, it was not difficult to be inspired. I could see it was possible to make something like that happen. I had been pretty low-key about my own racquet design but Mr. Sommer saw the racquet cases I had been carrying around and he asked if I would show him. The design was a long way from production and at the time I was somewhat nervous about the design being stolen, but I was eager to show him anyway. I knew it would be smart to get his insight.
Air Pump for a Racquet ?!
When I first pulled out the prototypes, he noted that they didn't look any different than a normal racquet but they were heavy. They did look normal at first glance and they were heavy because the innovation was on the inside of the racquet. The next thing I pulled out of the case got his attention, an air pump! With a chuckle he asked if it had something to do with the racquet. In some way he expected me to say no because it wasn't obvious, but when I said yes and connected the pump to an air valve sticking out slightly from the bottom of the handle, his eyes popped out of his head. Now, he was serious and silent as I pumped air into the racquet. As the pressure increased, the strings pinged and popped, the string tension was increasing as the pressure rose. He couldn't believe his eyes and ears. By the time I finished pumping (180-200 psi), the string-bed was floating on a cushion of air inside the racquet.
After holding the prototype and tapping at the strings a bit to confirm what he witnessed, he said something like (paraphrase), "If you can work it out for mass production it will make a great racquet, maybe the best racquet, but I don't see how you will manufacture this. It will be impossible." He was right on both accounts. He was an engineer so he knew right away it would make a great racquet because he understood the principle of suspension, and clearly he understood how it applied to racquets. He may have also known, like I did as a fellow inventor, that engineers had been pursuing a commercially viable string suspension design in racquets for over one hundred years so if and when it could be worked out for mass production, it would be huge.
Mr. Sommer said the prototype racquet would be impossible to manufacture. Of course he was right again, to have a racquet with an air pump and the potential to leak for example would be ridiculous, but that wasn't my objective. My objective was the floating string-bed using air but the only way I knew to get the air inside was to pump it in. I wasn't pursuing adjustable tension, as many engineers had over the years (see "Bergelin Long-String", Macgregor-DeLorean), it was for me merely the means to get the string-bed floating. In other words, I knew the prototype design could be greatly simplified so I was far more confident than Mr. Sommer that there was a valid product ahead.
Mr. Sommer may have also understood at the time, like I did, that if string suspension could be worked out in a commercially viable product, it would make the Kinetic design "technologically obsolete". A fully suspended string-bed absorbs vibration (and impact shock) before it transfers to the frame, making absorption of vibration and shock from inside the frame, as the Kinetic design does, unnecessary. As I've found since, string suspension greatly improves upon the Kinetic in stability and "plow-through" as well. However, in spite of his understanding, Mr. Sommer was not concerned in the least. He understood the huge challenge ahead and he knew it would be a long time before string suspension and a floating string-bed in a racquet would become a commercial reality.
That week made a big impact on me. It confirmed I was on the right track and it confirmed my suspension design was significant, worth pursuing and that I was capable of getting it done. It's one reason why BOLT exists today. Practically speaking, I learned a lot from Mr. Sommer about developing and manufacturing racquets. And in watching the Kinetic Launch event with Mr. Laver as Chief VIP, I learned a bit about marketing racquets too.
From a design standpoint I left with invaluable knowledge of mass production which helped to move my project forward. Up to that point my design experience was primarily in the field of architecture. The rationale of fabrication and assembly is certainly similar from industrial design to architecture, but the production processes are different. Each process has its own parameters and in order to design for mass production, I needed to know those parameters. Hearing Mr. Sommer describe them in detail was one of the best ways I could learn.
There was a great deal of work ahead in refining my concept and I didn't know exactly where it was headed, but I know the beautiful simplicity of the Kinetic strip itself left an imprint in my mind. As I developed and simplified my design, I'm certain the imprint helped me envision the final version and arrive at the ultimate solution - Zipstrip !
It's taken many years as Sommer predicted, but the potential positive impact of string suspension for players and for the game itself is extraordinary and well worth its pursuit toward the long-term health of tennis. Even though the Zipstrip and the era of string suspension has finally materialized and now competes with the Kinetic racquet, I hope Mr. Sommer would be glad to know he helped inspire a solution for a breakthrough and the great new racquet design paradigm which comes with it. (With respect and admiration, BOLT takes aim at the Kinetic!)